The present invention relates to physical exercise equipment, in particular to a novel apparatus for strength training.
In strength training, the isokinetic technique which requires movement at constant speed and at peak force throughout the full range of motion is proven to be most effective. Hydraulic cylinders are commonly used in this type of exercise equipment. Since its generated resistance increases with increasing speed, it can provide to the user the resistance up to his maximum capacity and limit his motion to the speed determined by his peak force. The employment of hydraulic cylinders has the following major short comings:
* The speed of the motion is difficult to set and monitor without a sophisticated and expensive control system.
* At high speed operation, the device must be set so that the resistance increases gradually with the increasing speed. Therefore, any slight change of force can produce a large variation in speed; as a result, the motion is not truly isokinetic.
* Resistance is a function of the speed, therefore at the beginning of the motion, there is no resistance generated to provide a desirable prestretch which is required to mobilize more muscle fibers into the contraction.
* It does not provide resistance as the muscles extend. This eccentric exercise technique in which the muscles are subjected to tension as they extend is very important in some training programs for many sports.
In eccentric training, the muscles need to extend slowly under applied force at near muscle peak resisting capacity. Generally the muscle can resist a load of 40% higher than its pulling capacity. Therefore, to train with this technique using weight as a means of generating negative load, the trainee needs to have an assistant to move the load to the starting point of each repetition. Beside the inconvenience, it can be very dangerous if the trainee gets fatigues and cannot withstand the load during the routine.
The present invention provides a novel approach to isokinetic and eccentric strength training exercise equipment which resolves all of the above shortcomings.